I am at 11:33 in.
Wooden gears and linear positioning. Conjugate profiles.
Here is a Linear position system that's low cost, precision, low wear.
I wanted to use Low cost off the self parts. This means no precision machined Steel.
I stumbled on the Roller Pinion System (see below) I wondered if I could do this in reverse.
To use a Roller Chain or set of Rollers (which could be ball bearing rings and a spacer in to an Aluminum L extrusion)
Roller Pinion System - The Reverse of what I want to do.
Two or more rollers engage the rack teeth in opposition at all times eliminating backlash. There is no tooth slap as with traditional rack and pinion, instead the RPS rollers approach the tooth face in a tangent path and then roll smoothly down the tooth face. This provides a smooth, quiet, low friction, fatigue free, high-efficiency rotary to linear motion conversion.
https://en.wikipedia.org/wiki/Mount_Washington_Cog_RailwayMount Washington in New Hampshire, USA
Sylvester Marsh was issued a U.S. patent for the general idea of a rack railway in September 1861,
- http://www.google.com/patents/US33255 US33255 A Sep 10, 1861